<!DOCTYPE html>
<html>
    <head lang="en">
        <meta charset="UTF-8">
        <title></title>
        <style>
            .ui-selected{
                background-color: hotpink;
            }
        </style>
        <script src="https://apps.bdimg.com/libs/jquery/2.1.4/jquery.min.js"> </script>
        <script src="jquery-ui.min.js"> </script>
        <script> 
        $(document).ready(function(){
            $("#btn").button();
            $("#select").selectable();
            $("#btn").on("click",function(){
                if($("#right").hasClass("ui-selected")){
                    alert("恭喜你答对了！")
                   
                    
                }
                else{
                    alert("你答错了")
                }
            });
        });
        </script>
        <link rel="stylesheet" href="jquery-ui.min.css">
    </head>
    <body>
        
        <strong>世界上最美丽的人是？</strong>
        <ul id="select">
            <li id="right"></li>
            <li>西施</li>
            <li>杨贵妃</li>
        </ul>
      <a href="#" id="btn">提交</a>
    </body>
</html>